This application claims the benefit under 35 U.S.C. xc2xa7120 or 35 U.S.C. xc2xa7365(c) of PCT International application PCT/CA99/00697 designating the United States of America, and filed Jul. 30, 1999, of which this application is a national stage filing under 35 U.S.C. xc2xa7371, was published under PCT Article 21(2) in English.
Foreign priority benefits are claimed under 35 U.S.C. xc2xa7119(a)-(d) or 35 U.S.C. xc2xa7365(b) of Canadian application number 2,244,453 filed Jul. 31, 1998, which designated at least one country other than the United States.
This invention relates to a new or improved method and apparatus for manufacturing a tobacco product in an unsmokable form, but in such a way that the user can readily convert them to smokable cigarettes.
For many years a certain segment of the smoking population has, for either economic or aesthetic reasons, preferred to smoke a self-made cigarette rather than the more conventional and more popular machine-made variety of cigarette.
While originally, self-made cigarettes were assembled by the smoker shaking loose cut tobacco onto a rectangular sheet of cigarette paper and then fashioning the sheet into a tube, over the years various appliances and systems have been developed to enable the smoker to produce a more regular style of self-made cigarette. Some aids that have in the past been devised for facilitating the self-made cigarette fabricating process have enjoyed commercial success. However in terms of product quality even the best of them has scarcely been able to produce an adequate substitute for a machine-made cigarette. There is however an ongoing demand for supplies for self-made cigarettes which at least in part is due to the more favourable tax treatment (as compared to conventional machine-made cigarettes) which these enjoy in some jurisdictions.
Our Canadian Patent 2,184,035 issued Jun. 15 1999 describes and illustrates embodiments of non-smokable tobacco products which can easily be converted by the smoker into a smokable cigarette. Amongst the most easily used embodiments described in the aforesaid patent are those which provide a tobacco-bearing component such as a rod-shaped tobacco element in combination with a filter element arranged end-to-end therein, said component having over part of its length an air-permeable surface area such as a porous filter surface rendering the component non-smokable. This component is provided in combination with a sliding tubular band carried on and closely surrounding the surface of the component. To render the product smokable, the user need merely slide the tubular band along the component to a position where it covers the air-permeable area. Such a non-smokable cigarette is considered by some to be vastly superior to all other forms of self-made cigarette supplies by virtue of its ease of use, and the close similarity of the finished product to a machine-made cigarette.
The present invention is concerned with the manufacture of self-made cigarette supplies as discussed in the preceding paragraph.
The invention provides a method of manufacturing a tobacco product in non-smokable form, comprising: providing a tobacco bearing component having a rod-shaped tobacco element, said component being non-smokable by virtue of the presence of an air-permeable area in the peripheral surface thereof extending over a minor portion in the length of said component; and enclosing said component in a tubular band of flexible sheet material of low permeability to the passage of air therethrough, said tubular band closely surrounding said component, being at a longitudinally offset position with respect to said air-permeable area, and being manually displaceable along said component to a position covering said air-permeable area to an extent sufficient to render said tobacco product into smokable condition.
The tobacco-bearing component may be in various forms, but preferably includes a filter fixed end-to-end with a tobacco rod, the latter being enclosed in a tube of regular cigarette paper, the air-permeable area being provided as a porous surface on the periphery of the filter, thus rendering the product unsmokeable.
A preferred assembly method involves applying a preformed tubular band onto the tobacco bearing component by arranging said tubular band and said tobacco-bearing component in axial alignment, and effecting relative axial movement towards one another of said tubular band and said tobacco-bearing component to bring these into engagement while effecting a slight compression of said tobacco rod to ease entry thereof into the interior of the tubular band, and sliding said tubular band to a desired location in the length of said tobacco rod. Radial compression of one end of the tobacco-bearing component to a size slightly smaller than the diameter of the tubular band enables the latter to be slid easily onto the tobacco-bearing component. Upon release of the compression force, the tobacco-bearing component is resiliently restored to its normal extent (which is of a circumference closely matched to that of the preformed tubular band) so that the latter will not accidentally shift along or fall off the tobacco-bearing component, but on the other hand can be slid therealong with minimal effort on the part of the user.
From another aspect, the invention provides an apparatus for assembling a preformed tubular band of filter cover material onto a preformed tobacco-bearing component which comprises a filter fixed end-to-end with a tobacco rod, said apparatus comprising: a first guide to receive said tubular band; a second guide to receive said tobacco rod; an assembly cylinder positioned between and in axial alignment with said first and second guides, said assembly cylinder having at a first end thereof adjacent said first guide an entry bushing which has a bore of a length and diameter corresponding to that of the filter cover, and at a second end an introducer bushing that has a bore substantially corresponding to the outer diameter of said tobacco rod, and between said entry bushing and said introducer bushing a sizing disc having a bore that tapers in the direction towards said entry bushing adjacent which it has a diameter that is smaller than the diameter of said entry bushing bore; said apparatus including a first movable member that is engageable with said tubular band to advance it along said first guide towards and into the assembly cylinder, and a second member that is engageable with said tobacco rod to advance the latter along said second guide towards and into said assembly cylinder.
Preferably a series of assembly cylinders with associated first and second guides and first and second axially movable members in the form of rods are provided distributed around the periphery of a rotatable drum. At a feed station the tubular band and the tobacco rod are supplied successively into the respective guides and are carried thereby as the drum rotates, axial movement of the rods being effected by stationary cams with which the rods are operatively connected.
In addition to the slight compression of the end of the tobacco rod that is effected by the sizing disc, it is preferred also to include at each assembly cylinder means for applying vacuum to the outer periphery of the end of the tubular band that first approaches the tobacco rod. In this way an expanding force is applied to that end of the tubular band to compensate for any slight malformations that may be present, and to ease the initial engagement with the end of the tobacco rod.